Take-up mechanism for sheet-feeding apparatus



1967 H. ROBINSON 7 3,357,651

TAKE-UP MECHANISM FOR SHEET'FEEDING APPARATUS Filed March 4, 1966 Hlr um... HIHHHIHI- I ml INVENTOR United States Patent 3,357,651 TAKE-UP MECHANISM FOR SHEET-FEEDING APPARATUS Harry Robinson, Kansas City, Mo., assignor to Flexipak, Inc., St, Louis, Mo. Filed Mar. 4, 1966, Ser. No. 531,948 11 Claims. (Cl. 242-65) This invention relates to sheet-feeding apparatus and, more particularly, to take-upmechanism for winding a continuously fed sheet of material.

In sheet-handling apparatus, it is often necessary to wind a continuously fed sheet of material onto a takeup roller or drum for packaging of the sheet in roll form. It is difiicult to uniformly wind the sheet to form a compact roll because the longitudinal tension of the sheet will vary as it is being fed from a feed roller or other source and consequently the sheet may be partially loosely wound and partially tightly wound. Additionally, the sheet will often have a tendency to travel oif the edge of the tak-up roller resulting in uneven edges on the formed roll of sheet material.

Heretofore, various methods have been tried for obviating this winding problem and they generally involved controlling and adjusting the tension of the sheet between its feeding source and the take-up roller. However, the results have not been acceptable, particularly in view of the fact that the apparatus has not been well suited for manual control by an operator who is vi wing the feeding operation and adjusting the tension as the sheet is wound on the take-up roller.

Therefore, it is the primary object of my invention to provide a take-up mechanism for sheet-handling appa ratus which is designed to inherently overcome the problems outlined above and thereby provide mechanism for winding continuously fed sheet material into a uniformly wound roll with a minimum of operator eifort being required.

A more particular object of the invention is to provide a take-up mechanism for sheet-handling apparatus which utilizes novel eccentric means for adjusting the tension of a sheet being continuously fed to a take-up roller and being Wound thereon. The provision of the eccentric means makes it possible for an experienced operator to accurately and easily control the tension in the feeding sheet and thus a uniformly wound roll is obtained.

An important object of the instant invention is to provide a take-up mechanism of the aforementioned charac ter which also incorporates means for varying the tension of the sheet on either end of the take-up roller as it is wound thereon. Thus, if the sheet tends to travel oh. the edges of the roller, the tension may be variably adjusted with respect to the ends of the roller to cause the sheet to re-align itself. Again, the adjustments are easily made by the operator and the overall operation of the mechanism is highly advantageous.

My invention has particular use in the winding of thin plastic film material such as that used for packaging fruit and various other food products. The sheet is preferably wound .into a roll which is free from loosely or tightly wound portions, as the former result in a disordered, hard to handle, bulky roll, while the latter give a stretching and consequent weakening of the plastic material.

Other objects include details of construction which will become apparent from the following specification and accompanying drawing, therein:

FIGURE 1 is a side elevational view of a sheet-handling machine incorporating the novel take-up mechanism of my invention;

FIG. 2 is a fragmentary, end elevational view thereof; and

3,357,651 Patented Dec. 12, 1967 FIG. 3 is a cross-sectional view taken along line 33 of FIG. 2.

The take-up mechanism of the present invention is adapted for use with sheet-handling apparatus, such as that illustrated in the drawing. The sheet-handling apparatus broadly comprises a base 10 having mounted thereon a source 1 2 of sheet material, a perforating structure 14, take-up mechanism 16 and drive means 18.

Source -12 includes a roller support 20 mounted on the top 22 of base 10, there being a feed roller 24 rotatably carried by support 20. Feed roller 24 initially carries a roll 26 of sheet material 28 circumferentially wound thereon.

Perforating structure 14 includes a pair of opposed, upstanding side plates 30 substantially centrally mounted on top 22 of base 10. A primary perforating drum 32 is journalled for rotation between plates 30, drum 32 presenting an outer, circumferential surface 34. A secondary perforating drum 36 is also journalled for rotation between side plates 30 and is positioned above and in engagement with primary drum 32. A guide roller 38 is mounted for rotation between side plates 30 and is disposed below primary drum 32. Perforating drums '32 and 36 are operably connected for rotation to drive means 18 by use of a chain 40 and associated gear mechanism 41.

Take-up mechanism 16 is also mounted on top 22 of base 10 and is disposed in spaced relationship to feed roller 24 with perforating structure 14 mounted therebetween. Take-up mechanism 16 includes a shaft 42 extending transversely across top 22 and disposed thereabove by shaft supports 44. A pair of opposed, spaced, L-shaped support brackets 46 are pivotally mounted on shaft 42 for shifting toward and away from feed roller 24. Each bracket 46 includes a transversely L-shaped leg 48 having a hub 50 on the inner surface of the free end portion of leg 48 and journalled about shaft 42.

A take-up roller 52 having an outer circumferential surface 53 is rotatably mounted between brackets 46 by a pair of tapered stub shafts 54 extending inwardly from the outer free end of corresponding legs 56 of brackets 46. Tapered shafts 54 are in the form of frusto-conical sections and extend into respective openings in the opposed ends of take-up roller 52.

Each bracket 46 is provided with shifting means, broadly designated by the reference numeral 57. Each shifting means 57 includes a lever 58 which is pivoted intermediate its ends on shaft 42 and is disposed in opposed relationship to hub 50 of bracket '46. A collar 60 is rigidly secured to lever 58 and is journal-led about shaft 42 for pivotal movement with lever 58. A sleeve 62 is rigidly secured to shaft 42 adjacent each of the collars 60 to prevent transverse shifting of take-up mechanism 16 on top 22 of base 10.

In each shifting means 57, one end 64 of lever 58 is provided with a plurality of openings 66 which are adapted to receive one end of a coil spring 68, the opposite end of spring 68 being secured to leg 56 of the corresponding bracket 46. The opposite end 70 of lever 58 rotatably receives an eccentric 72 by means of a shaft 74. Eccentric '72 is circular in configuration and the axis of shaft 74 is spaced from the geometric center thereof. An upstanding operating arm 76 is rigidly secured to eccentric 72. Eccentric 72 has a peripheral cam surface 78 which rests on top 22 of base 10.

In operation, drive means 18 is actuated to rotate chain 40 which, through its associated gear mechanism 41, causes drums 32 and 36 to rotate. The outer surface 53 of take-up roller 52 is positioned to engage the outer surface 34 of drum 32 and is rotated thereby through frictional contact. Thus, as is clear from FIG. 1, as drum 32 is rotated in a counter-clockwise manner, drum 36 and take-up roller 52 will be rotated in a clockwise direction.

A roll 26 of sheet material 28 is pre-wound on feed roller 24 to serve as a source of continuously feeding sheet material. It will be appreciated that my invention may be adapted for use with virtually any continuously feeding sheet operation, whether or not sheet 28 is in roll form. The outer end of roll 26 is threaded around the lower edge of guide roller 38 and then directed between guide roller 38 and perforating drum 32, whereupon sheet 28 is caused to travel in a counterclockwise direction along surface 34 of drum 32 until it is guided between drums 32 and 36 for a perforating operation. The perforated sheet then continues along surface 34 until coming into contact with take-up roller 52 and then, due to the frictional engagement of take-up roller 52 with drum 32, sheet 28 is pulled therebetween to be wound about take-up roller 52 in a clockwise direction to form a perforated sheet roll 80. It will be understood that the perforating operation is shown here merely as an example of one use of my novel take-up mechanism.

As roll 26 is being unwound and formed into perforated roll 80, the longitudinal tension of the sheet material 28 between feed roller 24 and take-up roller 52 will generally inherently vary as the operation proceeds. If there is a low tension, the sheet will be relatively loosely wound upon take-up roller 52 and conversely, if the tension is relatively high, sheet 28 will be tightly wound on take-up roller 52. To eliminate this undesired result, take-up mechanism 16 may be adjusted by an operator to control the amount of tension in the feeding sheet.

In this regard, to increase the tension in the sheet, operating arms 76 are pulled by an operator standing at the proximal end of base whereupon eccentrics 72 will be caused to rotate in a counterclockwise direction and cam surfaces 78 will cooperate with base 10 by rolling along top 22 thereof. Shafts 74 and their associated ends 70 of levers 58 will simultaneously raise to pivot levers 58 about shaft 42 which results in a stretching of springs 68 tending to pull legs 56 of brackets 46 downwardly. As springs 63 act on leg 56, take-up roller 52 will be forced into greater frictional engagement with driven drum 32 and thereby increase the pull on sheet material 28 to increase the longitudinal tension therein.

Conversely, to decrease the tension in sheet 28, the operator will push operating arms 76 forwardly, resulting in a compression of springs 68, thereby tending to force legs 56 of brackets 46 upwardly. Manifestly, this results in a slight upward movement of take-up roller 52 to decrease the frictional engagement of the same with drum 32 and, accordingly, will decrease the pull on sheet material 28. Maximum compression in springs 68 will occur when that portion of cam surface 78 radially aligned with shaft 74 is engaged with top 22.

An experienced operator viewing the feeding operation will be table to determine the relative tension and winding properties of sheet material 28. When variations occur, he need only pull or push on operating arms 76 to shift take-up roller 52 with respect to drum 36 and source 12 to readjust the pull on the sheet and thus provide a substantially uniformly wound roll 80 of sheet material 28. Because of the novel provision of eccentrics 72, very little physical effort is required of the operator and, therefore, he may operate the machine for a prolonged period of time without tiring and is thereby able to consistently produce a quality product.

In the event that sheet material 28 becomes misaligned as it travels on drum 32 and is thereby caused to travel off the edge of take-up roller 52, the operator may correct this error by varying the relative tension transversely of the roll. This is accomplished by, for example, pushing one operating arm 76 while pulling the other which, respectively, decreases the tension on one side of take-up roller 52 while increasing it at the other. This variation in tension, when properly applied, will transversely pull the sheet toward the operating arm 76 which is being pulled and thereby providing higher tension. The operator may, therefore, selectively align sheet material 28 as it is delivered from drum 32. It will be noted that take-up roller 52 will slightly rock on shafts 54 to permit the above described limited independent movement of the opposed ends of the roller.

After roll has been completed, take-up roller 52 may be easily replaced by constructing at least one of the stub shafts 54 to be removable from its corresponding bracket 46. Thus, when one stub shaft 54 is removed, the mounted take-up roller 52 is slipped from the other stub shaft 54 and a new take-up roller may be inserted by telescoping one of the axially aligned openings in the ends thereof over the frusto-conical shaft 52 and then replacing the removed shaft 52.

To adapt the take-up mechanism of the present invention to various sizes and types of sheet material, the tension of springs 68 may be adjusted by moving the proximal ends thereof to any one of the number of openings 66 in levers 58.

Having thus described the invention, what is claimed as new and desired to be secured by Letters Patent is:

1. Take-up mechanism for winding sheet material which is continuously fed from a source, said mechanism comprising:

a base;

a take-up roller;

shiftable structure rotatably mounting said roller on said base to receive the continuously fed sheet; apparatus for supporting and rotating said take-up roller to wind said sheet; and

means mounted on said base for shifting said roller with respect to said sheet feeding source to adjust the tension in the sheet, said shifting means including a biasing member interconnecting said base and said shiftable structure, a rotatable eccentric operably coupled to said shiftable structure and means for rotating said eccentric, the eccentric being cooperable with said base so that when said eccentric is rotated, said structure will shift against the force of said biasing member to shift said take-up roller.

2. Mechanism as set forth in claim 1, wherein said rotating apparatus comprises a driven roller rotatably mounted on said base with the outer surface thereof in frictional contact with the outer surface of the take-up roller, there being means for rotating said driven roller and for directing said sheet between said rollers at the contacting surfaces thereof for pulling the sheet therethrough and thereby winding the sheet on said take-up roller, said shifting means being coupled to said structure for shifting said take-up roller toward and away from said driven roller to vary the frictional engagement therebetween to vary the pull on the sheet and thereby the tension therein.

3. Mechanism as set forth in claim 1, there being a pair of said shiftable structures, each having corresponding rotating apparatus, shifting means and rotating means, said structures being positioned at respective opposed ends of said roller.

4. Mechanism as set forth in claim 3, wherein each of said shiftable structures comprises a bracket pivotally mounted on said base for swinging movement toward and away from the sheet-feeding source to effect said shifting movement.

5. Mechanism as set forth in claim 4, wherein each of said shifting means includes a lever pivotally mounted intermediate its ends on said base, said biasing member interconnecting said bracket and one end of said lever, the other end of said lever being rotatably mounted on said eccentric at a spaced distance from the geometric center of the eccentric so that when said eccentric is rotated, said lever will pivot against the force of'said biasing member to shift said bracket and thereby said take-up roller.

6. Mechanism as set forth in claim 5, wherein said eccentric is substantially circular in configuration and the peripheral, outer surface thereof is positioned to engage said base so that when said eccentric is rotated it will simultaneously roll on said base and pivot said lever.

7. Mechanism as set forth in claim 6, wherein said rotating means comprises a manually operated lever rigidly secured to said eccentric.

8. Mechanism as set forth in claim 5, wherein said biasing member comprises a coil spring.

9. Take-up mechanism for winding sheet material which is continuously fed from a source, said mechanism comprising:

a base;

a take-up roller having axially aligned openings in the opposed ends thereof;

a pair of opposed shiftable brackets mounted on said base and having means thereon for rotatably receiving said take-up roller therebetween, said means comprising a pair of opposed frusto-conical stub shafts each extending and tapering inwardly from a respective bracket and telescoped into a corresponding opening in said take-up roller; and

a pair of shifting means mounted on said base for individually shifting respective brackets and thereby said roller with respect to said sheet feeding source to adjust the tension in the sheet, said shafts permitting limited independent movement of the opposed ends of said roller when said shifting means are operated.

10. Take-up mechanism for winding sheet material which is continuously fed from a source, said mechanism comprising:

a base;

a shaft supported on said base;

a take-up roller;

a pair of opposed, spaced brackets pivotally mounted on said shaft and having means thereon for rotatably receiving said take-up roller therebetween;

apparatus for supporting and rotating said take-up roller to wind said sheet; and

a pair of shifting means mounted on said base for shifting respective brackets and thereby said roller with respect to said sheet feeding source to adjust the tension in the sheet, each of said shifting means comprising a lever pivotally mounted intermediate the ends thereof on said shaft, a biasing member interconnecting one end of said lever and its corresponding bracket, an eccentric rotatably mounted on the other end of said lever at a spaced distance from the geometric center of the eccentric and means for rotating said eccentric, the eccentric cooperating with said base so that when the eccentric is rotated, said lever will pivot against the force of said biasing member to shift said bracket and thereby said takeup roller.

11. Take-up mechanism for winding sheet material which is continuously fed from a source, said mechanism comprising:

a base;

a take-up roller;

a pair of opposed spaced brackets shiftably mounted on said base and having means thereon for rotatably receiving said take-up roller therebetween;

a driven roller rotatably mounted on said base with the outer surface thereof in frictional contact with the outer surface of the take-up roller for rotating the latter, there being means for rotating said driven roller and for directing said sheet between said rollers at the contacting surfaces thereof for pulling the sheet therethrough and thereby winding the sheet on said take-up roller; and

a pair of shifting means mounted on said base for shifting respective brackets and thereby said roller with respect to said driven roller, each of said shifting means including a biasing member interconnecting said base and a respective bracket, a rotatable eccentric operably coupled with said bracket and means for rotating said eccentric, said eccentric being cooperable with said base so that when said eccentric is rotated, said bracket will shift against the force of said biasing member and thereby said take-up roller will correspondingly shift toward and away from said driven roller to vary the frictional engagement therebetween to vary the pull on the sheet and thereby the tension therein.

References Cited UNITED STATES PATENTS 2,223,445 12/1940 Doble 242-57.1 2,872,126 2/ 1959 Rockstrom et al 242 LEONARD D. CHRISTIAN, Primary Examiner. 

1. TAKE-UP MECHANISM FOR WINDING SHEET MATERIAL WHICH IS CONTINUOUSLY FED FROM A SOURCE, SAID MECHANISM COMPRISING: A BASE; A TAKE-UP ROLLER; SHIFTABLE STRUCTURE ROTATABLY MOUNTING SAID ROLLER ON SAID BASE TO RECEIVE THE CONTINUOUSLY FED SHEET; APPARATUS FOR SUPPORTING AND ROTATING SAID TAKE-UP ROLLER TO WIND SAID SHEET; AND MEANS MOUNTED ON SAID BASE FOR SHIFTING SAID ROLLER WITH RESPECT TO SAID SHEET FEEDING SOURCE TO ADJUST THE TENSION IN THE SHEET, SAID SHIFTING MEANS INCLUDING A BIASING MEMBER INTERCONNECTING SAID BASE AND SAID SHIFTABLE STRUCTURE, A ROTATABLE ECCENTRIC OPERABLY COUPLED TO SAID SHIFTABLE STRUCTURE AND MEANS FOR ROTATING SAID ECCENTRIC, THE ECCENTRIC BEING COOPERABLE WITH SAID BASE SO THAT WHEN SAID ECCENTRIC IS ROTATED, SAID STRUCTURE WILL SHIFT AGAINST THE FORCE OF SAID BIASING MEMBER TO SHIFT SAID TAKE-UP ROLLER. 